This invention relates generally to computed tomography (CT) imaging and more particularly, to reducing cone beam artifacts in CT images.
The original Feldkamp, Davis, and Kress (FDK) algorithm for a circular trajectory has been extensively employed in medical and industrial imaging applications. With increasing cone angle, cone beam (CB) artifacts associated with the FDK algorithm deteriorate, because a circular trajectory does not satisfy the so-called data sufficiency condition (DSC). A few “circular plus” trajectories, such as “circle+circle”, “ellipse+ellipse”, “circle+line”, “circle+arc”, have been proposed to facilitate reducing CB artifacts by meeting the DSC. However, the circular trajectory possesses advantages in medical imaging, such as perfusion, cardiac and vascular imaging, as well as breast and head imaging applications.